Menozzi M, von Buol A, Itschner L, Saluz L, Krueger H
Institut für Hygiene und Arbeitsphysiologie, ETH Zürich.
Z Morphol Anthropol. 1996 Sep;81(2):205-15.
Different cephalometric lines or planes may be used to determine vertical head tilt. 94 subjects were used to assess the difference in inclination between the Frankfurt horizontal and Reid's line by means of a photographic method. We found that the inclination of Reid's line differs about 13 degrees from the inclination of the Frankfurt horizontal and depends on the subject's sex but not on their age. Hand held inclinometer are used in most studies for determining the inclination of the head. In our study different experimenters assessed the above mentioned inclinations at our 94 subject's using a hand held inclinometer. It turned out that the results depend statistically significant on the experimenter. Data were compared to the ones assessed using the photographic method. By means of an analysis of variance in which the experimenter is considered, a significant correlation (p < 0.001) between data assessed with the two different methods was found. However, only 51% of the variance can be explained by our model. Variance might be due to inaccuracy in determining some of the points defining the Frankfurt horizontal and Reid's line, i.e. the lower orbit and the centre of the outer ear channel. The inclination of another reference line running from the tragion to the outer canthus was measured using the same subjects and the same experimental procedure as mentioned above. This line is easier to determine than the Frankfurt horizontal or Reid's line as its defining points can be assessed with greater accuracy. The inclination of this differs 10.5 degrees from the one of the Frankfurt horizontal.
不同的头影测量线或平面可用于确定头部垂直倾斜度。94名受试者通过摄影方法评估了法兰克福水平线与里德线之间的倾斜度差异。我们发现，里德线的倾斜度与法兰克福水平线的倾斜度相差约13度，且取决于受试者的性别而非年龄。大多数研究使用手持倾角仪来确定头部的倾斜度。在我们的研究中，不同的实验者使用手持倾角仪对94名受试者的上述倾斜度进行了评估。结果发现，结果在统计学上显著依赖于实验者。将数据与使用摄影方法评估的数据进行了比较。通过考虑实验者的方差分析，发现两种不同方法评估的数据之间存在显著相关性（p < 0.001）。然而，我们的模型只能解释51%的方差。方差可能是由于确定定义法兰克福水平线和里德线的某些点（即下眼眶和外耳道中心）时不准确所致。使用与上述相同的受试者和相同的实验程序，测量了另一条从外耳道前点到外眦的参考线的倾斜度。这条线比法兰克福水平线或里德线更容易确定，因为其定义点可以更准确地评估。这条线的倾斜度与法兰克福水平线的倾斜度相差10.5度。
